Ladder jack



Oct. 25, 1949. c ARMSTRONG v 7 2,485,685

LADDER JACK Filed April 15. 1946 INVENTOR. 65752455 fleMsrpan/a Patented Oct. 25, 1949 UNITED STATES PATENT OFFICE LADDER JACK Charles Armstrong, Denver, 0010. Application April 15, 1946, Serial No. 662,176

2 Claims.

This invention relates to devices for removable and adjustable association with conventional runged ladders to facilitate the operative security and convenience, and to enhance the utility, thereof, and has as an object to provide an improved such device adaptable to a wide variety of specific practical uses in association with a ladder.

A further object of the invention is to provide an improved construction and operative arrangement of elements constituting a jack for removable and replaceable, adjustable association with conventional ladders.

A further object of the invention is to provide an improved ladder jack employable as a strut to space the upper end of an associated ladder outwardly from and in supported relation with a substantially vertical surface.

A further object of the invention is to provide an improved ladder jack employable to minimize lateral slipping of an associated ladder upper end relative to and along an arcuate-surfaced, substantially vertical, supporting wall or element.

A further object of the invention is to provide an improved ladder jack adapted to conveniently function as a ladder-associated bracket for the support of planks, shelves, and analogous scaffold elements.

A further object of the invention is to provide an improved ladder jack conveniently engageable in securely-positioned, readily-adjustable relation with conventional ladders.

A further object of the invention is to provide an improved device of ladder jack type that is simple and inexpensive of manufacture, compact and convenient in form, practical throughout a wide range of specific uses, readily adaptable in a few standard sizes to operative conformity with all usual types and sizes of conventional runged ladders, and which is sturdy in proportion to its bulk and weight.

With the foregoing and other objects in view, my invention consists in the construction, arrangement, and combination of elements hereinafter set forth, pointed out in my claims, and illustrated by the accompanying drawing, in which- Figure 1 is a perspective view of a typical, simple embodiment of the invention as positioned and arranged for operative association in one a'djusted relation with a ladder. Figure 2 is a front elevation of the device according to Figure l, certain extending elements being broken away to conserve space. Figure 3 is a top plan view, on a reduced scale, of the device according to Figure 1 with certain of the movable elements of the device at one extreme of their range of adjustment and the brace member broken away. Figure 4 is a view similar to Figure 3 illustrating an alternative adjusted position of certain of the device movable elements. Figure 5 is a side elevation of a typical ladder equipped with a pair of alternately-arranged, reduced-scale specimens of the improvement. Figure 6 is a fragmentary,-detail, side elevation and Figure 7 a fragmentary, detail, bottom plan view of a hook construction advantageously employable in substitution for the analogous constructions of Figure 1. Figure 8 is a fragmentary, detail, side elevation and Figure 9 a fragmentary, detail, bottom plan view of yet another hook construction alternatively employable in and with the improvement.

In the construction of the improvement as shown, a preferably integral, substantially U-shaped, rigid yoke is formed, as by bending opposite end portions of a straight metallic strap or bar into spaced parallelism perpendicular to the bar portion intercepted therebetween, to present a fiat, straight base element l0 fixedly engaged with and between a pair of like arms ll extending in spaced parallelism from the opposite ends and in perpendicular relation with the length of said element. The specific size, shape, and character of material from which the element In and arms H are formed may be proportioned to the contemplated use requirements of the device at the time of yoke fabrication, and the spacing between the arm I l free ends is preferably correlated at the time of yoke manufacture with the width dimension of conventional runged ladders so that said arm free ends may be simultaneously entered between the stiles 12 of such a ladder and engage the opposite end portions of a rung l3 thereof to mount the yoke with its element H) in hinged, parallel relation with the so-engaged rung, the said arm I I free ends being formed or provided with laterally-opening notches I4, or hook elements hereinafter to be described, for reception of and cooperation with the engaged rung [3 end portions.

I-Iingedly connected at one of its ends tothe midportion of the element It) inner face, as by means of an eye 15 or equivalent member secured to said element, a longitudinally-adjustable brace I6 is associated with and to swing through a vertical arc in a plane perpendicular to that of the yoke. The free end of the brace I6 is equipped with rung-engaging means, such as an offset hook l1, adapted to clip over and hold its function with various specific ladders and.

with various inclinations of a given ladder, pro

vision must be made for selective adjustment of,

the brace l6 effective length, for which purpose the said brace may consist of separate; slidably= associated sections adapted forxlocked or inter-relation in various positions of relative adjustment, the notch and detent arrangement illustrated as suitable for a toggle-joint type bracebeingbut representative of a wide range of I functionally-equivalent length adjustments extensively 1 heretofore. commonly:- known and; used;

Complete as thusifarldescribed; the improvement :imadequate-fdr ra number of specific uses helpful to those-Who workron .and from ladders andtladder-supported scaffolding: Mounted with its-yoke proj ecting. horizontally from the upper end rungJofaladder at anobtuse angle with-the ladder stiles; the -improved 'jack 'functions efii ciently as a strutv 'engageable'= against a supporting wall 'orasurface tospacethe ladder endoutwardly therefrom and as a bracket for the support" of material,' tools, and the like. Associated with intrmediaterungs-of= a ladder; and on either sidethereof,-'thexdevice providesseither an open or a closed bracket, depending upontherelative disposition of "the brace' it} available for support of -material,-scafiolding, tools and facilities, andfor use-as a workman s seat wwith consequent obvious convenience and advantagew Enlarging thefunctions and 1 extending the improvement, similar; complementary shoes I 3, each formed withan outturned v end "lug-l9; are slidahly-sec-ured against and-forutility of the adjustment longitudinal-ly along the outer face of the element 10 with their end lugs l9 parallel-toand directed oppositely-from=thearms l L1 Each of the shoes l 8 is associated with for which purpose it is convenient toform each sh'oe i 8 with an elongateylongitudinalslot in slid ably-embracing" "relationwith aheaded-bolt 20- engaged throughtheelement H3 half for cooperation-of its inner threaded end-with a'wing-nut' 2i',-or like adjustable clamping agent, adapted tobear against the element inner "face; As somounted, the shoes l8-may-'be=shifted' along; I ii and selectively clamped thereto to vary the spacing-between the end-lugs id as may) be desired wi hin the operative-range provided by the slots, and-"said'shoes may be'rctated'about the 'element the "bolts '26 to'bring their lug ends-into adjustably-spaced'juxtaposition; as shown in-Figure 4,

according to the operative needs and problems When so 'equipped; the

to be met by the device. end'lugs I901" the assembly serve as contact points of reduced'area engageable agai-nst a fiat wallorsupporting-surface to space-the ladder end-and element I outwardly therefirom when the device clamped-i.

a half of the element it at one side of the-eye i and'is -independently secured to-saidelement in-a=manner permitting cal-longitudinal shifting and end for end reversal of the-shoe 'relative-to-said element,

is used as aspacing strut," thereby facilitatingpainting and other surfacing of the supporting Wall, and in positions of properly spaced adjustment, said end lugs l9 operate to engage against convex surfaces of large radius, Figure 3, and on the opposite sides of trees, poles, and the like, Figure 4, for the support of a ladder upper end thereagainst in a manner that minimizes the hazard of lateral slipping.

While the device, in simple form, is illustrated as equippedwith laterally-,opening,1plain notches I 4 and a simple, open hook lT'for engagement with the rungs I3 of a ladder, the invention contemplates provision of means on the free ends of;the arms II and brace It for secure latchable engagement with the ladder rungs, typical such means being illustrated in Figures 6, 7, 8 and 9. As shoWn:;in:;Figur es 6 and 7, a downwardlyopening, rung-engageable hook 22 may be upwardly'offset from the arm i l or brace it free end in closable cooperation with a manually-adjustable-latch bar Zilpivotally carried by'the arm or brace adjacent the throat of saidihook and in" position to at i-times obstruct saidthroat beneath an: engagedrung and thereby inhibit uninten tional= disengagement of the hook from said-rung,-

while in Figures 8 and the hook-22 is intersected:

by one or-more holes 24 may be engaged said hook to pass either partiallyor entirely through said rung and secure the --hook 'against accidental displacement.-

Since many changes, variations, and modifications in the specific form, construction, andarrangement of the elements *shown and described may be had Without'departing from the spirit of my invention, I 'wish'to'be understood as being through which-a-nail or pin with the rung embraced by limitedsolely by the-scope"of the appended claims, rather than by-any details of the illustrative showing and foregoing-description.

I claim as my invention:

1. In a ladder jack, a unitary; U-shaped yoke member having -a flat, elongate base and like integral arms projecting in spaced parallelism perpendicularly-from the base ends, hooks adjacent the 'free ends of said arms engageable with the opposite end portions of a ladder rung to hingedly mount said yoke with" its the engaged rung, a brace hinged to the yoke midportion andselectively' engageable at its free end'with a'ladderrung either above or below. that engaged-by saidiyoke: arms to operatively support said yoke insubstantiafly horizontal projection from the associatedtladder with the yoke base face in opposition'to a'vertical surface to-. ward which the ladder is inclined,llike shoes spaced apart in slidableandmotatable bearing engagement against"; the yoke base means forclampingsaid'shoes to said base in base parallel to outer face,

any-position of theirrela'tive adjustment thereon,

said shoes.

2. In-a ladder jack: havinga U-shaped yoke member formed with a fiat,'elongate base operatively paralleling the rungsof. ladder andflmeans for supporting and outturned;vertical=surface-engaging ends on an. associated said yoke on;

and in substantially horizontal projection from a ladderwith the yokelbase faceinopposition'to ,a vertical surface outer face for secure;ladder-supportingengage-- toward which ..theladder is inclined--,:means adj ustably carried-by the yoke base ment with vertical surfaces of varyingtype and contour," saidmeans comprising:-

pair I of flatshoes spaced -apart'in slidable engagement against- ,1 the: base outer face, an el'ongate -slot in -each ofsaid shoes, a bolt received through each of said slots and a registering hole in the yoke base, a clamp nut on each of said bolts, and an outturned end lug on each of said shoes.

CHARLES ARMSTRONG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Bauer June 6, 1876 Wheeler June 19, 1900 Jones Nov. 27, 1900 Stiles Nov. 11, 1902 Bauer Jan. 16, 1912 Kramer Mar. 30, 1926 

